This invention relates generally to marine hatcheries and related equipment and processes. More specifically, the present invention concerns an abalone farming system which utilizes horizontally elongated, vertically stacked culturing tanks.
Abalone, a rock-clinging gastropod mollusk that has a flattened shell slightly spiral in form, lined with mother-of-pearl, and with a row of apertures along its outer edge, has increasingly become a sought-after delicacy in many fine restaurants. This has led, in recent years, to the creation of abalone farms, wherein the abalone are hatched, raised to maturity and then sold to restaurants and restaurant suppliers.
Most abalone farms are located adjacent to a salt water source, such as an ocean, and include a hatchery and a separate growout unit. In the hatchery, the abalone are grown in tanks under controlled conditions to a size between 0.25 inch and 0.50 inch diameter. The abalone are then transferred to the growout area where conditions are less controlled and are grown there to a size typically between 2.00 inches and 3.25 inches diameter.
In prior abalone farming systems, the hatchery is often located within a building equipped with large racks for supporting large, typically circular water basins. These water basins provide growing tubs in which the baby mollusks feed on algae during the initial growth phase. An end of an air tube is often placed into the seawater in these basins to help aerate the water to provide a suitable growing environment for the young abalone.
After the young abalone have reached a sufficient size (0.25 inch to 0.50 inch diameter), they are transferred to outdoor growout tanks. These are typically large rectangular seawater catch basins which are supplied with kelp on which the abalone feed, as well as the algae which grows therein. These large outdoor water basins require much land because, unlike the tubs within the hatchery, they are not stacked one upon the another.
One drawback of prior abalone farming techniques lies in the space required to setup an efficient farming operation. Due to the nature of the tubs utilized in prior hatcheries, the hatchery itself must often be located in a multi-story building, wherein access to the upper tubs is available only by means of ladders. The outdoor growout area is, further, extraordinarily large in order to provide sufficient grazing area for the abalone. In both the hatchery and the growout area, control over the conditions under which the abalone are being raised is often less than ideal simply because the tanks are large, deep and inaccessible to ordinary inspection.
Accordingly, there has been a need for a novel abalone farming system which uses culturing tanks that provide a higher surface area for grazing than the prior hatchery tubs and growout area basins. Additionally, a need exists for an efficient abalone farming system which is at least partially self-cleaning, permits the abalone to be conveniently collected in a single location after being anesthetized, and provides closer control over algae growth within the tanks. Moreover, such a system is needed which permits control over water temperature and water quality. The present invention fulfills these needs and provides other related advantages.